1. Field of the Invention
The present invention relates to devices for dental radiographic procedures or intraoral diagnostics, and more particularly, to intraoral dental radiology positioning devices relating to positioning x-ray film or receptors in a patient's mouth during radiographic procedures.
2. Description of Related Art
Intraoral x-ray diagnosis involves positioning an x-ray film within a patient's mouth next to the inner surface of the teeth or bone being studied. The film is then exposed to an x-ray beam generated outside the mouth and passing through the target. Known intraoral dental radiography typically employs a dental device having an alignment member including an x-ray film holding structure at one end, an aligning arm at another end, and a bite plate positioned between the ends. The alignment member (also known as an aiming ring) may include a collimation structure for collimation of an x-ray beam to conform more accurately to the size and shape of the x-ray film held by the film holding structure. A commonly prescribed dental radiograph is the “bitewing”, whereby an image is acquired of the crowns of the teeth biting together and their surrounding socket bone. Also typical is film mounted in a holder that includes a bite block portion extending from the film in the direction of the external x-ray tube. The patient bites down on the bite block with the target teeth and holds the film in position next to the target.
Many dental radiographic techniques utilize beams of circular cross-section despite the fact that the dental films are typically rectangular in shape. A disadvantage of known devices is that the cross-sectional area of the beam used by the radiographic technique is typically larger than the surface area of the x-ray film. When the cross-sectional area of the beam does not match the film size, the patient can be exposed to unnecessary radiation that irradiates tissues beyond the borders of the dental film. Typical film positioning instruments may also allow unwanted x-radiation to pass through the film holding instrument.
Another disadvantage of current x-ray film positioning instruments is that there can be errors in aiming the x-ray. These errors are frequently associated with a rectangular position-indicating device attached to an x-ray machine. Also, there can be errors in orientation of the long axis of the substantially rectangular typical position indicating devices with the long axis of the film in the patient's mouth. Aiming and orientation errors expose the patient to needless retakes of radiographs. Moreover, if a rectangular positioning device is used, it must be specifically oriented for vertical or horizontal receptor orientation, and must be re-positioned if the receptor orientation is changed.
A further disadvantage of current x-ray film positioning instruments is that the patient can only bite on the bite plate to assist in positioning and holding a film positioning device in the mouth. Typical devices may be difficult to grasp and manipulate in the patient's mouth making it problematic for the patient to assist in positioning the instrument, particularly during the x-ray exposure itself.